a conglomeration or encrustation on the surface of an object; occurs especially during the corrosion of metals.
Synonyms in English
Much of the discussion surrounding concretions comes from the underwater archaeology profession, as well as the conservators who specialize in and treat materials that have been underwater. It is important to consider that the layers of concretion and corrosion products can build up on an object so much that the original form can be lost. Additionally, the original object can deteriorate so much that a concretion becomes entirely hollow.
There are a variety of treatment methods for objects with concretions. Colin Pearson notes that mechanically cleaning larger objects with chisels, dental tools, and vibrations after an X-ray (in order to identify original material) is usually the safest route. He goes on to mention that the use of chemicals to dissolve concretions should only be done within a lab setting (Pearson 1987).
Bartosz A. Dajnowski has experimented with laser ablation techniques to remove concretions (Dajnowski).
Dajnowski, B. Laser ablation cleaning of an underwater archaeological bronze spectacle plate from the H.M.S. DeBraak shipwreck. University of Delaware Program in Art Conservation.http://www.bartoszdajnowski.com/uploads/1/8/9/3/18930255/8790-58__dajnowski.b..pdf